1. Field of the Invention
The present invention relates to a method for producing propylene oxide. More particularly, the present invention relates to a method for producing propylene oxide by reacting a hydroperoxide with propylene by a fixed bed flow reaction in the presence of a titanium-containing solid catalyst to improve the selectivity of the intended propylene oxide and to suppress the decomposition of the hydroperoxide.
2. Description of the Related Art
Propylene oxide is one of useful industrial chemicals used for example as a raw material in producing a polyurethane, and the like.
It is known that an olefin-type compound and an organic hydroperoxide are reacted in the presence of a titanium-containing solid catalyst to convert the olefin-type compound into an oxirane compound. The titanium-containing solid catalyst used is usually prepared by a method in which titanium is supported on a silica carrier and the like (see, e.g., Japanese Patent Application Publication (JP-B) Nos. 56-35941, 54-40525, 54-40526 and 50-30049, Japanese Patent Application Laid-Open (JP-A) No. 8-269031, and the like). However, when an epoxidation reaction of propylene is conducted by a fixed bed flow reaction by using a catalyst prepared by these methods, there occurred problems that a unpreferable by-product was formed and the selectivity of propylene oxide was insufficient, and that the decomposition reaction of a hydroperoxide was accelerated due to heat generation.